<canvas id="canvasID" width="400" height="400">Canvas not supported</canvas>
<div id="map"></div>
<script>
    //Animation from https://javascript.tutorials24x7.com/blog/how-to-draw-animated-circles-in-html5-canvas
    var canvas = document.getElementById('canvasID');
    var ctx = canvas.getContext('2d');
    var circles = [];
    var radius = 20;

    function Circle(x, y, dx, dy, radius, color) {
        this.x = x;
        this.y = y;
        this.dx = dx;
        this.dy = dy;

        this.radius = radius;

        this.draw = function() {
            ctx.beginPath();
            ctx.arc(this.x, this.y, this.radius, 0, Math.PI * 2, false);
            ctx.strokeStyle = color;
            ctx.stroke();
        };

        this.update = function() {
            if (this.x + this.radius > 400 || this.x - this.radius < 0) {
                this.dx = -this.dx;
            }

            if (this.y + this.radius > 400 || this.y - this.radius < 0) {
                this.dy = -this.dy;
            }

            this.x += this.dx;
            this.y += this.dy;

            this.draw();
        };
    }

    for (var i = 0; i < 5; i++) {
        var color =
            '#' +
            (0x1000000 + Math.random() * 0xffffff).toString(16).substr(1, 6);
        var x = Math.random() * (400 - radius * 2) + radius;
        var y = Math.random() * (400 - radius * 2) + radius;

        var dx = (Math.random() - 0.5) * 2;
        var dy = (Math.random() - 0.5) * 2;

        circles.push(new Circle(x, y, dx, dy, radius, color));
    }

    function animate() {
        requestAnimationFrame(animate);
        ctx.clearRect(0, 0, 400, 400);

        for (var r = 0; r < 5; r++) {
            circles[r].update();
        }
    }

    animate();

    var map = new mapboxgl.Map({
        container: 'map',
        zoom: 5,
        minZoom: 4,
        center: [95.899147, 18.088694],
        style: 'mapbox://styles/mapbox/streets-v11'
    });

    map.on('load', function() {
        map.addSource('canvas-source', {
            type: 'canvas',
            canvas: 'canvasID',
            coordinates: [
                [91.4461, 21.5006],
                [100.3541, 21.5006],
                [100.3541, 13.9706],
                [91.4461, 13.9706]
            ],
            // Set to true if the canvas source is animated. If the canvas is static, animate should be set to false to improve performance.
            animate: true
        });

        map.addLayer({
            id: 'canvas-layer',
            type: 'raster',
            source: 'canvas-source'
        });
    });
</script>
